https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98581
Richard Biener <rguenth at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Version|unknown |11.0 Last reconfirmed| |2021-01-07 Status|UNCONFIRMED |NEW Ever confirmed|0 |1 Target| |aarch64 --- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> --- There's nothing invalid here and I guess you are simply "unlucky" (or have bougs expectations). This looks like a "perfect" opportunity for a pre-expand pattern match to a direct internal fn corresponding to this instruction which can look at the whole addition chain (short of integrating this matching into the late reassoc pass).